code: def _normalize_image(image: tf.Tensor) -> tf.Tensor:
      """Normalize the image to zero mean and unit variance."""
      image -= tf.constant(MEAN_RGB, shape=[1, 1, 3], dtype=image.dtype)
      image /= tf.constant(
          STDDEV_RGB, shape=[1, 1, 3], dtype=image.dtype
      )
      return image
  
file_path: objax/examples/image_classification/imagenet_resnet50_data.py
imports: import enum
  from typing import Optional, Sequence, Tuple
  import jax
  import numpy
  import tensorflow.compat.v2
  import tensorflow_datasets
label_desc: Use image node_id 6 for calling a global function with example usage: _normalize_image(image) and returns: image